Spinoza and the Cartesian Divide

The artificial intelligence discourse has recreated, without recognizing it, the exact problem Baruch Spinoza solved in the seventeenth century: the Cartesian split between mind and matter, between the ghost and the machine, between the thing that thinks and the thing that moves. René Descartes divided the world into two substances—res cogitans, thinking stuff, and res extensa, extended stuff—and the division has haunted every serious attempt to understand whether machines can think. Spinoza's dissolution was radical and remains unimproved: there is only one substance, and mind and body are not two things that interact but the same thing expressed under two attributes, Thought and Extension. This is the metaphysical foundation on which the AI project rests, usually without acknowledgment: substrate independence—the principle that mind is portable across physical media—is Spinoza's monism translated into the language of functionalism. Yet the same doctrine that licenses the project forbids its cheapest conclusions: that any sufficiently complex computation is therefore